I took a 40x4 character LCD out of an old word processor i had, and I'm trying to figure out how to interface with it. I found that it had a 14 pin interface, 8 oki m5259 chips, and 2 larger unlabeled chips, both the same size. A bit of googleing led me to believe that it was a standard 14 pin LCD. I began trying to figure out what order the pins were numbered, so I started probing around the host device with a multimeter. I found some odd things. The Vcc pin (the only pin +5v on it in the host device) was located as such on the LCD:
(o = pin, v = Vcc)
o o o o o o o o o o v o o o
other than the +5v pin, most other pins had no voltage, however some had around 2v. Because of the positioning of the Vcc pin, it seems that it is not following the standard 14 pin LCD design, however it could just be a non-standard pin ordering. Messing around I have noticed that I can get rows 1 and 3 of the LCD to light (this same thing seems to happen as the LCD starts in the host device) if I connect +5v (v). ground (G), and ground (g) as such:
o o o o o o o o g o v G o o
I can also get the same effect with 'g' on several other pins, provided v and G don't move. Does anyone have any suggestions as to how I can determine the interface to this LCD. Note, that at the moment I simply want to connect up some dip switches and mess with it that way, then eventually get a PIC in on it.
Lastly, as a side-note, I wanted to know if its a good idea for me to be using an ATX psu as a workbench power source, for this and other project?